1. Field of the Invention
This invention relates to steel cords usable for the reinforcement of rubber article bodies such as pneumatic tires, industrial belts and the like. More particularly, it proposes an improvement in the steel cord of so-called compact structure composed of steel filaments in connection with developmental results for greatly enhancing the durable life of the rubber article by improving fatigue properties, particularly resistance to material fatigue and fretting wear, and strength retaining properties of the steel cord. It and is particularly suitable as a reinforcement of pneumatic radial tires for truck, bus and light truck.
2. Related Art Statement
In a conventional pneumatic radial tire using steel cords as a reinforcement, the fatigue properties of the carcass ply and belt layer are degraded mainly by the following causes: